<!DOCTYPE html>
<html lang="zh">
	<head>
		<meta charset="UTF-8">
		<meta name="viewport" content="width=device-width, initial-scale=1.0">
		<meta http-equiv="X-UA-Compatible" content="ie=edge">
		<title></title>
	</head>
	<body>
		
	</body>
	<script type="text/javascript">
		// ES6 允许给函数参数赋值初始值
		
		//1.形参初始值  具有默认值的参数,一般位置要靠后
		
		function add(a,b,c=10){	//形参赋初始值
			return a + b + c;
		}
		let result = add(1,2);
		console.log(result);//13
		
		function add2(a,b,c=10){
			return a + b + c;
		}
		let result2 = add(1,2,3);
		console.log(result2);//6
		
		function add3(a,b,c){
			return a + b + c;
		}
		let result3 = add3(1,2);
		//2.与解构赋值结合
		function connect({host="127.0.0.1",username,password,port}){
			console.log(host);
			console.log(username);
			console.log(password);
			console.log(port);
		}
		connect({
			// host:"www.baidu.com",// 如果没有赋值  走上面的默认值
			username:"百度",
			password:"123",
			port:3306
		})
	</script>
</html>
